Biotin contents have been determined for relatively few foods and are not ordinarily included in food composition tables. Although biotin is widely distributed in natural foodstuffs, its concentration varies substantially. For example, liver contains biotin at about 100 µg/100 g whereas fruits and most meats contain only about 1 µg/ 100 g.
The U.S. Department of Agriculture Continuing Survey of Food Intakes by Individuals, the Third National Health and Nutrition Examination Survey (NHANES III), and the Boston Nutritional Status Survey do not report biotin intake. Murphy and Calloway (1986), using food intake data from the NHANES II, estimated the mean biotin intake of young women aged 18 to 24 years to be 39.9 ± 26.9 (standard deviation) µg/day. This result is considerably lower than the estimated dietary intake of biotin in a composite Canadian diet (62 µg/day) and an actual analysis of the diet (60 µg/day) (Hoppner et al., 1978). Calculated average intakes of biotin for the British population of adults and children were similar to the U.S. estimate—33 and 35 µg/day (Bull and Buss, 1982; Lewis and Buss, 1988).
According to the 1986 National Health Interview Survey, approximately 17 percent of U.S. adults take a supplement containing biotin (Moss et al., 1989). Specific data on intake from supplements are not available.
No reported adverse effects of biotin in humans or animals were found. Toxicity has not been reported in patients treated with daily doses up to 200 mg orally and up to 20 mg intravenously to treat biotin-responsive inborn errors of metabolism and acquired biotin deficiency (Mock, 1996).